<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>typeof操作符</title>
</head>
<body>
    <p>typeof操作符返回变量或表达式的类型。</p>
    <p id="demo"></p>
<script>
    document.getElementById("demo").innerHTML =
            typeof "john" + "<br>" +
            typeof 3.14 + "<br>" +
            typeof false + "<br>" +
            typeof [1,2,3,4] + "<br>" +
            typeof {name:'john',age:34};
</script>
</body>
</html>